Invalid broker uri when starting apache activemq

I downloaded apache activemq version 5.9 on Windows 7, then opened command prompt and typed ACTIVEMQDIR> .\bin\activemq

and got an error Invalid Broker URI

.

What configuration information do I need to provide in order for activemq to work on Windows 7?

EDIT: Here's the stack trace:

C:\activemq\bin>activemq start /p
Java Runtime: Oracle Corporation 1.7.0_79 C:\Program Files\Java jdk1.7.0_79\jre
Heap sizes: current=1005568k free=989808k max=1005568k
JVM args: -Dcom.sun.management.jmxremote -Xms1G -Xmx1G -Djava.util.logging.c
onfig.file=logging.properties -Djava.security.auth.login.config=C:\activemq\bin\
..\conf\login.config -Dactivemq.classpath=C:\activemq\bin\..\conf;C:\activemq\bi
n\../conf;C:\activemq\bin\../conf; -Dactivemq.home=C:\activemq\bin\.. -Dactivemq
.base=C:\activemq\bin\.. -Dactivemq.conf=C:\activemq\bin\..\conf -Dactivemq.data
=C:\activemq\bin\..\data -Djava.io.tmpdir=C:\activemq\bin\..\data\tmp
Extensions classpath:
[C:\activemq\bin\..\lib,C:\activemq\bin\..\lib\camel,C:\activemq\bin\..\lib\op
tional,C:\activemq\bin\..\lib\web,C:\activemq\bin\..\lib\extra]
ACTIVEMQ_HOME: C:\activemq\bin\..
ACTIVEMQ_BASE: C:\activemq\bin\..
ACTIVEMQ_CONF: C:\activemq\bin\..\conf
ACTIVEMQ_DATA: C:\activemq\bin\..\data
Loading message broker from: /p
ERROR: java.lang.RuntimeException: Failed to execute start task. Reason: java.la
ng.IllegalArgumentException: Invalid broker URI, no scheme specified: /p
java.lang.RuntimeException: Failed to execute start task. Reason: java.lang.Ille
galArgumentException: Invalid broker URI, no scheme specified: /p
at org.apache.activemq.console.command.StartCommand.runTask(StartCommand
.java:91)
at org.apache.activemq.console.command.AbstractCommand.execute(AbstractC
ommand.java:57)
at org.apache.activemq.console.command.ShellCommand.runTask(ShellCommand
.java:150)
at org.apache.activemq.console.command.AbstractCommand.execute(AbstractC
ommand.java:57)
at org.apache.activemq.console.command.ShellCommand.main(ShellCommand.ja
va:104)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.
java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.activemq.broker.BrokerFactory.createBroker(BrokerFactory.